Dwivedi 2017.

Study characteristics
Methods	2‐arm RCT Single‐centred, conducted in hospital settings at Boston Medical in India Duration of follow‐up was a maximum of 9 weeks
Participants	60 participants  enrolled: stated that 44 participants with 44 wounds completed the study Ten participants were withdrawn from the NPD group due to deterioration of pressure ulcer with possible wound infection, or because the individual’s natal cleft area disrupted the vacuum, or owing to the refusal of additional treatment. In addition, 6 participants withdrew from the comparison group and refused additional treatment. Therefore, data from 44 patients were analysed Inclusion criteria listed: individuals with spinal cord injury and paraplegia; patients aged 16 to 60 years and stage III to IV pressure ulcer as defined by the National Pressure Ulcer Advisory Panel (NPUAP) 2016 taxonomy for pressure ulcer staging Exclusion criteria listed: pressure ulcers with necrotic tissue that could not be removed on baseline debridement, chronic osteomyelitis, exposed blood vessels and nerves in the wound, and specific comorbid conditions likely to impair wound healing such as diabetes mellitus, rheumatoid disease, and vasculitis; patients undergoing chemotherapy or radiation therapy and persons with severe nutritional deficits (Braden Scale score for Pressure Sore Risk Nutrition subscale score of ≤2, a serum.albumin level of <2.5 g/L, or a haemoglobin level of <9.0 g/L)
Interventions	Group A: negative pressure device (NPD). The unit also includes a connecting tube with clamp, a “Y” connector, a curved needle with a matching catheter, and a spare perforated catheter (Romo Vac Set GS‐5002 SIZE‐10; Romsons Scientific and Surgical Industries Pvt Ltd, Agra, Uttar Pradesh, India). The wound dressing was a sterilized piece of foam and transparent polyurethane adhesive dressing (Opsite; G. Surgiwear Ltd, Shahjahanpur, Uttar Pradesh, India) to ensure the airtight seal needed to exert negative pressure. The NPD dressing was changed weekly or more often if the dressing became saturated or loss of suction occurred. The NPD dressing was changed by the same investigator throughout the study. Group B:  The wound was gently cleansed to remove debris from the wound bed, and saline‐soaked gauze was placed lightly inside the bed, which was covered with a sterile dry dressing. Dressings were changed once or twice daily depending upon the volume of exudate and saturation of the dressing.
Outcomes	Primary outcomes: none Secondary outcomes: surface area (reported as length and width separately). PUSH scores (reported as depth, exudate, and tissue type separately).
Notes	Funding source: no details of funding sources.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "Study group location was completed using a computer‐generated random table." Comment: adequate
Allocation concealment (selection bias)	Unclear risk	No information
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Quote: "All clinical assessments on a given patient were made by the same investigator throughout the study, and all data collectors received standardized training concerning data collection procedures." Comment: no detailed information
Incomplete outcome data (attrition bias) All outcomes	High risk	Quote: "Ten participants were withdrawn from the NPD group due to deterioration of PI with possible wound infection, or because the individual’s natal cleft area disrupted the vacuum, or owing to refusal of additional treatment. In addition, 6 participants withdrew from the comparison group and refused additional treatment. "
Selective reporting (reporting bias)	Low risk	Comment: reported data on all outcomes stated in the methods
Other bias	High risk	We found that the data used in the two studies were similar (CTRI/2014/09/0050), but there was a difference in the number of people included in the intervention group and the control group. We contacted the author to request more detailed information, but no reply was received.